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The Grey Analysis, Kriging and Selection Index of Flower Yield in Rugosa Rose 被引量:6
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作者 LI Yan-yan FENG Zhen ZHAO Lan-yong MO Zhen-hua ZHANG Bao 《Agricultural Sciences in China》 CAS CSCD 2007年第12期1420-1425,共6页
The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant (FY) and 15 other quantitative traits of 20 rugosa ro... The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant (FY) and 15 other quantitative traits of 20 rugosa rose cultivars. The result showed that: The grey relational grade (GRG) of the number of flowers/plant (NF), the number of branches/plant (NB), the width of floral bud (WB), and the weight/flower (WF) to the FY were larger (〉 0.5); FY improved with the increase of NF and NB. Moreover, the indirect selection of either trait could not achieve improvement of FY. It is necessary to improve FY by multi-trait selection. The integration selection index (ISI) equation of FY was established with the characters NF, NB, WB, and WF: I= 0.3187x1 - 318.6x2 + 670.1 x4 + 6.3xa, index heritability = 0.8014, selective response of the integration breeding value = 245.8811. This will provide a theoretic basis for the genetic breeding of rugosa rose. 展开更多
关键词 rugosa rose grey relational grade quantitative traits kriging interpolation index selection
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Spatial/temporal indexing and information visualization genre for environmental digital libraries 被引量:3
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作者 CHEN Su-shing GRUNWALD Sabine 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第11期1235-1248,共14页
Protecting and preserving our environmental systems require the ability to understand the spatio-temporal distri- bution of soils, parent material, topography, and land cover as well as the effects of human activities... Protecting and preserving our environmental systems require the ability to understand the spatio-temporal distri- bution of soils, parent material, topography, and land cover as well as the effects of human activities on ecosystems. Space-time modelling of ecosystems in an environmental digital library is essential for visualizing past, present, and future impacts of changes occurring within such landscapes (e.g., shift in land use practices). In this paper, we describe three novel features, spa- tio-temporal indexing, visualization, and geostatistical genre, for the environmental digital library, Environmental Visualization and Geographic Enterprise System (ENVISAGE), currently in progress at the University of Florida. 展开更多
关键词 Spatio-temporal indexing GEOSTATISTICS giS (Geographic Information System) Visualization Environmentaldigital library Spatio-temporal search
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杂粮的有效利用——低GI(Glycaemic Index)食品的必要性(英文) 被引量:1
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作者 片山直美 《中国粮油学报》 EI CAS CSCD 北大核心 2007年第6期64-70,共7页
研究了在体重过多人群的食生活里导入杂粮的有效性以及杂粮食谱的营养价值。营养价值参考了日本厚生劳动省发表的"日本人食事摄取基准",这资料标示了目标热量、各种营养成分的目标摄取量以及许多项目的极限程度。因为极限程... 研究了在体重过多人群的食生活里导入杂粮的有效性以及杂粮食谱的营养价值。营养价值参考了日本厚生劳动省发表的"日本人食事摄取基准",这资料标示了目标热量、各种营养成分的目标摄取量以及许多项目的极限程度。因为极限程度与年龄、性别和生理状态有关,在此我们以普通生活的成人作为基准。杂粮中的营养成分,苋的热量358kcal、蛋白质12.7g、脂肪6.0g、糖质64.9g、食物纤维7.4g、Na 1.0mg、P540mg、Fe 9.4mg、Ca 160mg、K 600mg、Cu 0.92mg、Zn 5.8mg、Mn 6.14mg、维生素A 2.0ug以及微量的维生素C。经过研讨设计了营养平衡最佳的食谱为:糙米200g、苋50g、andeskinua50g、大豆110g、甘薯200g、绿黄色蔬菜(小青菜)300g、鸡蛋55g以及泥鳅100g。食用这个食谱可以摄取热量2007 kcal(是基准摄取量的100%),其他营养成分的摄取量与基准摄取量相比分别为:蛋白质173%、脂肪72%、碳水化物105%、K 332%、Ca262%、Mg 267%、P 250%、Fe 420%、Zn 183%、Cu 343%、VA 126%、VD 100%、VE 142%、VK 940%、VB1237%、VB2174%、烟碱酸201%、VB6218%、VB12375%、叶酸350%、泛酸160%、VC 176%、食物纤维185%、盐分5%以及Mn 273%。不足的盐分可以使用调味料来补充。氨基酸的摄取量推测是基准值的100%。蛋白质:脂肪:碳水化物的比例是19.0∶18.0∶63.0,与理想的平衡比接近。 展开更多
关键词 杂粮 gi(Glycaemic index) 营养平衡食物 超重人群
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Modelling of graded index waveguide fabricated by ion exchange on Er^(3+) doped glass 被引量:1
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作者 邵公望 金国良 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期1096-1104,共9页
A general numerical tool, based on thermal diffusion equation and full-vectorial eigen-mode equation, has been presented for the systematic analysis of graded index channel waveguide fabricated by ion exchange on Er^3... A general numerical tool, based on thermal diffusion equation and full-vectorial eigen-mode equation, has been presented for the systematic analysis of graded index channel waveguide fabricated by ion exchange on Er^3+ doped glass. Finite difference method with full-vectorial formulation (FV-FDM) is applied to solving the full-vectorial modes of graded index channel waveguide for the first time. The coupled difference equations based on magnetic fields in FV-FDM are derived from the Taylor series expansion and accurate formulation of boundary conditions. Hybrid nature of vectorial guided modes for both pump (980 nm) and signal light (1550 nm) are demonstrated by the simulation. Results show that the fabrication parameters of ion exchange, such as channel opening width and time ratio of second step to first step in ion exchange, have large influence on the properties of waveguide. By optimizing the fabrication parameters, maintenance of monomode for signal light and improvement of the gain dynamics can be achieved in Er^3+ doped waveguide amplifier (EDWA) fabricated by ion exchange technique. This theoretical model is significant for the design and fabrication of EDWA with ion exchange technique. Furthermore, a single polarization EDWA, which operates at wavelength from 1528 nm to 1541 nm for HE polarization, is numerically designed. 展开更多
关键词 graded index channel waveguide finite difference method full-vectorial mode ion exchange technique
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Monte Carlo Simulation on LED Graded-refractive-index Multilayer Encapsulation Structure 被引量:1
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作者 YU Renyong JIN Shangzhong LIANG Pei CEN Songyuan 《Semiconductor Photonics and Technology》 CAS 2010年第2期73-77,共5页
Light propagation in nanoparticle-loaded encapsulants is simulated based on the method of Monte Carlo,referring to the multilayer graded-refractive-index structure for LED encapsulants.And the influence of scattering ... Light propagation in nanoparticle-loaded encapsulants is simulated based on the method of Monte Carlo,referring to the multilayer graded-refractive-index structure for LED encapsulants.And the influence of scattering coefficient on the transmittance is analyzed.The results show that the transmittance decreases with scattering coefficient.For a given number of layers,the encapsulants will yield maximum transmittance if the refractive index value of each layer is optimized.The nanoparticle-loaded encapsulant consists of multiple layers with refractive-index values that gradually decrease.The transmittance will be higher than that of traditional non-graded encapsulants,and will improve light extraction efficiency of LED. 展开更多
关键词 light-emitting diode(LED) graded refractive index Monte Carlo simulation
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A Novel Hybrid Method for Measuring the Spatial Autocorrelation of Vehicular Crashes: Combining Moran’s Index and Getis-Ord G<sub>i</sub><sup style='margin-left:-7px;'>*</sup>Statistic 被引量:2
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作者 Azad Abdulhafedh 《Open Journal of Civil Engineering》 2017年第2期208-221,共14页
Spatial autocorrelation is a measure of the correlation of an observation with other observations through space. Most statistical analyses are based on the assumption that the values of observations are independent of... Spatial autocorrelation is a measure of the correlation of an observation with other observations through space. Most statistical analyses are based on the assumption that the values of observations are independent of one another. Spatial autocorrelation violates this assumption, because observations at near-by locations are related to each other, and hence, the consideration of spatial autocorrelations has been gaining attention in crash data modeling in recent years, and research have shown that ignoring this factor may lead to a biased estimation of the modeling parameters. This paper examines two spatial autocorrelation indices: Moran’s Index;and Getis-Ord Gi* statistic to measure the spatial autocorrelation of vehicle crashes occurred in Boone County roads in the state of Missouri, USA for the years 2013-2015. Since each index can identify different clustering patterns of crashes, therefore this paper introduces a new hybrid method to identify the crash clustering patterns by combining both Moran’s Index and Gi*?statistic. Results show that the new method can effectively improve the number, extent, and type of crash clustering along roadways. 展开更多
关键词 Spatial AUTOCORRELATION Moran’s index Getis-Ord gi* Statistic Vehicle Crashes
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Integrating Lithostratigraphic Units and GIS-Analysis Techniques to Modified Surface Water Quality Index 被引量:1
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作者 Majed Ibrahim Habes Al-Mashakbeh 《Journal of Environmental Protection》 2016年第8期1104-1112,共10页
The purpose of this study is to investigate the effect of using Bicarbonate and Calcium parameters as alternatives to the lithostratigraphic units covered the catchment area, on water quality index (WQI) values that h... The purpose of this study is to investigate the effect of using Bicarbonate and Calcium parameters as alternatives to the lithostratigraphic units covered the catchment area, on water quality index (WQI) values that have been implemented with GIS technique at Wadi Al-Arab Dam. The analyzed results (by WQI method) have been used to depict water quality for the two approaches. Based on physico-chemical parameters, the calculated values for WQI over the 3-year for study period were 169, 168, and 157, respectively. While the WQI values were 184, 183 and 172, respectively, as a result of incorporated Bicarbonate and Calcium parameters in WQI calculations that significantly contributed to increasing the WQI. The elevated values may be attributed to the influence of carbonate stone dissolution and mechanical erosion under weathering conditions that are prevalent during winter season in the catchment area. As a consequence of lithostratigraphic unites product and GIS technique integration and normalization processes, most of water quality ranks are good and only autumn season has poor water quality in the 2012 and 2013, while in 2014 it has good water quality in the same season. The WQI values increase in general trend from winter to autumn seasons during the study period that may be referred to outflow by daily consumption, evaporation rising, and seepage water. The analysis shows that the modified water quality values of the Wadi Al-Arab Dam Reservoir (WADR) vary after using Bicarbonate and Calcium parameters by constant value. Generally, the results signify that the WADR is not polluted based on the physical and chemical characteristics of water. 展开更多
关键词 giS Lithostratigraphic Units Water Quality index Surface Water Reservoir SEASONALITY Irbid Wadi Al-Arab Dam JORDAN
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基于GIS软件的县级耕地质量等别年度更新评价研究——以松桃县为例 被引量:2
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作者 韩朗 张梦棋 侯敬丽 《国土与自然资源研究》 2024年第1期1-4,共4页
本研究基于GIS软件的空间分析工具,通过选取适宜松桃县的耕地质量等别评定基本参数、评价指标体系及权重,采用“因素法”对2019-2020年度新增、减少类耕地及质量建设耕地等别变化范围进行评定。结果表明,2019-2020年,松桃县减少耕地面积... 本研究基于GIS软件的空间分析工具,通过选取适宜松桃县的耕地质量等别评定基本参数、评价指标体系及权重,采用“因素法”对2019-2020年度新增、减少类耕地及质量建设耕地等别变化范围进行评定。结果表明,2019-2020年,松桃县减少耕地面积871.02 hm^(2),新增耕地159.91 hm^(2),新增耕地等别集中在9~11,质量建设耕地226.26 hm^(2);与“三调”统一时点耕地质量等别成果对比,提升0.01等别。基于本次耕地质量等别成果动态更新,以期为地区实现耕地资源信息的社会化服务及自然资源数量质量并重管理提供参考。 展开更多
关键词 giS 耕地质量等别 更新评价 松桃县
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基于机-热-电多参量信号特征的GIS隔离开关状态评估方法 被引量:4
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作者 周秀 吴旭涛 +3 位作者 田天 白金 张昭宇 李军浩 《电力工程技术》 北大核心 2024年第1期220-228,共9页
气体绝缘开关(gas insulated switchgear,GIS)设备中的隔离开关故障往往是机械、热、电气多物理量综合作用的结果,从微小缺陷发展至严重故障的过程中,会产生异常振动、温度、局部放电多种参量信号,同时测量并分析GIS隔离开关的多参量信... 气体绝缘开关(gas insulated switchgear,GIS)设备中的隔离开关故障往往是机械、热、电气多物理量综合作用的结果,从微小缺陷发展至严重故障的过程中,会产生异常振动、温度、局部放电多种参量信号,同时测量并分析GIS隔离开关的多参量信息对于准确获取其运行状态具有重要意义。文中通过在实体220 kV GIS实验平台上模拟隔离开关最为常见的接触不良缺陷,研究不同接触状态时振动信号、温度变化和局部放电信号的演化规律,获得其与设备状态之间的对应关系,结合健康指数理论和改进层次分析法,提出基于多参量特征的GIS隔离开关综合评估方法。使用该方法开展现场测试,其检查结果与多参量综合评估方法的的分析结果相吻合。文中的研究为GIS隔离开关状态的带电检测提供了一种可行性较高的多参量融合分析新方法。 展开更多
关键词 气体绝缘开关(giS) 隔离开关 振动信号 温度变化 局部放电 健康指数:改进层次分析法
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Tunability of graded negative index-based photonic crystal lenses for fine focusing
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作者 晋蕾 朱清溢 付永启 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期391-394,共4页
Graded negative refractive index-based photonic crystal (PC) lenses are designed by gradually modifying the sizes of air holes along the transverse direction for focusing the incident plane wave. To study the tunabi... Graded negative refractive index-based photonic crystal (PC) lenses are designed by gradually modifying the sizes of air holes along the transverse direction for focusing the incident plane wave. To study the tunability of the graded negative index-based PC, we introduce filling factor A, gradually tune the filling factor, and use the finite-difference and time-domain (FDTD) algorithm for numerical calculation. Our calculation results indicate that the focal length and the spot size increase with A increasing. For the same A value, the focal length of a PC with elliptical air holes is the longest, and those of PC with square and rectangular air holes are the shortest. Moreover, when the focal length is greater than 1 ~xm, the focal parameters of the PC are highly insensitive to the variation of A. When the focal length is less than 1 gm, the PC lenses have higher transmittances and all well focus with a beam spot size breaking the diffraction limit. This feature possibly makes the graded negative index-based PC lenses have some new applications in optoelectronic systems. 展开更多
关键词 photonic crystals graded negative index FOCUSING flat lenses
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Flat lenses constructed by graded negative index-based photonic crystals with tuned configurations
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作者 晋蕾 朱清溢 +1 位作者 付永启 鱼卫星 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期267-271,共5页
Flat lenses are designed by means of graded negative refractive index-based photonic crystals (PCs) constructed using air-holes tuned with different shapes. By gradually modifying the filling factor along the transv... Flat lenses are designed by means of graded negative refractive index-based photonic crystals (PCs) constructed using air-holes tuned with different shapes. By gradually modifying the filling factor along the transverse direction, we obtain the graded negative index-based lenses for the purpose of focusing an incident plane wave. The finite-difference and timedomain (FDTD) algorithm is adopted for numerical calculation. Our calculation results indicate that these lenses can finely focus incident plane waves. Moreover, for the same size of air-holes, the focusing properties of the lens with rectangular air-holes are better than those with the other shaped air-holes. The graded negative index PCs lenses could possibly enable new applications in optoelectronic systems. 展开更多
关键词 photonic crystals graded negative index FOCUSING flat lenses
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Graded index broadband antireflection coating prepared by glancing angle deposition for a high-power laser system
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作者 孔伟金 沈自才 +3 位作者 王淑华 邵建达 范正修 卢朝靖 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期304-308,共5页
This paper reports that SiO2 is selected to fabricate broadband antireflection (AR) coatings on fused silica substrate by using glancing angle deposition and physical vapour deposition. Through accurate control of t... This paper reports that SiO2 is selected to fabricate broadband antireflection (AR) coatings on fused silica substrate by using glancing angle deposition and physical vapour deposition. Through accurate control of the graded index of the SiO2 layer, transmittance of thc graded broadband AR coating can achieve an average value of 98% across a spectral range of 300-1850 nm. Moreover, a laser-induced damage threshold measurement of the fabricated AR coating is performed by using a one-on-one protocol according to ISOl1254-1, resulting in an average damage threshold of 17.2 J/cm2. 展开更多
关键词 broadband antireflection coating graded index glancing angle deposition
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Graded index profiles and loss-induced single-mode characteristics in vertical-cavity surface-emitting lasers with petal-shape holey structure
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作者 刘安金 渠红伟 +4 位作者 陈微 江斌 周文君 邢名欣 郑婉华 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期247-254,共8页
The 850-nm oxide-confined vertical-cavity surface-emitting lasers with petal-shape holey structures are presented. An area-weighted average refractive index model is given to analyse their effective index profiles, an... The 850-nm oxide-confined vertical-cavity surface-emitting lasers with petal-shape holey structures are presented. An area-weighted average refractive index model is given to analyse their effective index profiles, and the graded index distribution in the holey region is demonstrated. The index step between the optical aperture and the holey region is obtained which is related merely to the etching depth. Four types of holey vertical-cavity surface-emitting lasers with different parameters are fabricated as well as the conventional oxide-confined vertical-cavity surface-emitting laser. Compared with the conventional oxide-confined vertical-cavity surface-emitting laser without etched holes, the holey vertical-cavity surface-emitting laser possesses an improved beam quality due to its graded index distribution, but has a lower output power, higher threshold current and lower slope efficiency. With the hole number increased, the holey vertical-cavity surface-emitting laser can realize the single-mode operation throughout the entire current range, and reduces the beam divergence further. The loss mechanism is used to explain the single-mode characteristic, and the reduced beam divergence is attributed to the shallow etching. High coupling efficiency of 86% to a multi-mode fibre is achieved for the single-mode device in the experiment. 展开更多
关键词 vertical-cavity surface-emitting lasers single mode low divergence angle graded index profile
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Design of wideband graded-index antireflection coatings at oblique light incidence 被引量:1
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作者 Zhang Jun-Chao Fang Ming +1 位作者 Jin Yun-Xia He Hong-Bo 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期199-203,共5页
We suggest a design method of graded-refractive-index (GRIN) antireflection (AR) coating for s-polarized or p- polarized light at off-normal incidence. The spectrum characteristic of the designed antireflection co... We suggest a design method of graded-refractive-index (GRIN) antireflection (AR) coating for s-polarized or p- polarized light at off-normal incidence. The spectrum characteristic of the designed antireflection coating with a quintic effective refractive-index profile for a given state of polarization has been discussed. In addition, the genetic algorithm was used to optimize the refractive index profile of the GRIN antireflection for reducing the mean reflectance of s- and p-polarizations. The average reflectance loss was reduced to only 0.04% by applying optimized GRIN AR coatings onto BK7 glass over the wavelength range from 400 to 800 nm at the incident angle of θo = 70°. 展开更多
关键词 antireflection coatings oblique incidence graded-refractive-index profile genetic algo-rithm
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Research of the Differential Uplifting in the Palongzangbu Region Based on the Synthesis of the Watershed Index and Seismic Data
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作者 Wang Lin Zhao Yan +2 位作者 Tian Qinjian Li Wenqiao Xu Yueren 《Earthquake Research in China》 CSCD 2018年第1期64-79,共16页
Research on the differential uplifting in the Palongzangbu region is crucial to understanding the tectonic deformation mechanism and establishing the model of the faulted blocks in the region of the east structural kn... Research on the differential uplifting in the Palongzangbu region is crucial to understanding the tectonic deformation mechanism and establishing the model of the faulted blocks in the region of the east structural knot.In this paper,based on the ASTER-30m DEM,we calculate the hypsometry index(HI)of 19 watersheds in the Palongzangbu region,and study the differential uplifting in this region combining with seismic data,the ground deposition and erosion process.The result shows that the spatial distribution of the HI value can reflect the differential uplifting in the study area.Differential uplifting exists within different zones,and there are 2 relative strong uplifting centers.One center is near the east structural knot,and the other lies between the Lhari fault and Nujiang fault at their converging segment.Also,the watershed evolution,seismic activity,and ground deposition and erosion process are closely related to each other,and they constitute a chain of evidence which reveals the whole process from the tectonic movement underground to the landform evolution on the surface. 展开更多
关键词 WATERSHED HYPSOMETRY index giS DEM Differential Tectonic UPLIFTING East Structural KNOT
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Detection and Mapping of Water Quality Variation in the Godavari River Using Water Quality Index, Clustering and GIS Techniques
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作者 Indrani Gupta Awkash Kumar +1 位作者 Chandrakant Singh Rakesh Kumar 《Journal of Geographic Information System》 2015年第2期71-84,共14页
The objective of this research is to develop a tool for planning and managing the water quality of River Godavari. This is achieved by classifying the pollution levels of Godavari River into several categories using w... The objective of this research is to develop a tool for planning and managing the water quality of River Godavari. This is achieved by classifying the pollution levels of Godavari River into several categories using water quality index and a clustering approach that ensure simple but accurate information about the pollution levels and water characteristics at any point in Godavari River in Maharashtra. The derived water quality indices and clusters were then visualized by using a Geographical Information System to draw thematic maps of Godavari River, thus making GIS as a decision support system. The obtained maps may assist the decision makers in managing and controlling pollution in the Godavari River. This also provides an effective overview of those spots in the Godavari River where intensified monitoring activities are required. Consequently, the obtained results make a major contribution to the assessment of the State’s water quality monitoring network. Three significant groups (less polluted, moderately and highly polluted sites) were detected by Cluster Analysis method. The results of Discriminant Analysis revealed that five parameters?i.e.?pH, Dissolved Oxygen (DO), Faecal Coliform (FC), Total Coliform (TC) and Ammonical Nitrogen (NH3-N) were necessary for analysis in spatial variation. Using discriminant function developed in the analysis, 100% of the original sites were correctly classified. 展开更多
关键词 giS Water Quality index CLUSTER ANALYSIS DISCRIMINANT ANALYSIS
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Evaluation of Groundwater Quality in the Deep Maastrichtian Aquifer of Senegal Using Multivariate Statistics and Water Quality Index-Based GIS
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作者 Djim M. L. Diongue Laila Sagnane +3 位作者 Huguette Emvoutou Maria Faye Ibra D. Gueye Serigne Faye 《Journal of Environmental Protection》 CAS 2022年第11期819-841,共23页
A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 bo... A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 boreholes distributed over the whole country. The aim was to 1) identify the water types and likely factors influencing the hydrochemistry, and 2) determine the suitability of groundwater for drinking and irrigation. Results showed that sodium, chloride, and fluoride are highly correlated with electrical conductivity (EC) reflecting the significant contribution of these elements to groundwater mineralization. The principal component analysis evidenced: 1) salinization processes (loaded by Na<sup>+</sup>, K<sup>+</sup>, EC, Cl<sup>-</sup>, F<sup>-</sup> and HCO<sub>3</sub>-</sup>) controlled by water/rock interaction, seawater intrusion and cation exchange reactions;2) dolomite dissolution loaded by the couple Ca<sup>2+</sup> and Mg<sup>2+</sup> and 3) localized mixing with upper aquifers and gypsum dissolution respectively loaded by NO<sub>3</sub>-</sup> and SO<sub>4</sub>2-</sup>. The hierarchical clustering analysis distinguished four clusters: 1) freshwater (EC = 594 μs/cm) with mixed-HCO<sub>3</sub> water type and ionic contents below WHO standard;2) brackish (Na-mixed) water type with moderate mineralization content (1310 μs/cm), 3) brackish (Na-Cl) water type depicted by high EC values (3292 μs/cm) and ionic contents above WHO and 4) saline water with Na-Cl water type and very high mineralization contents (5953 μs/cm). The mapping of the groundwater quality index indicated suitable zones for drinking accounting for 54% of the entire area. The occurrence of a central brackish band and its vicinity, which were characterized by high mineralization, yielded unsuitable groundwater for drinking and agricultural uses. The approach used in this study was valuable for assessing groundwater quality for drinking and irrigation, and it can be used for regional studies in other locations, particularly in shallow and vulnerable aquifers. 展开更多
关键词 Groundwater Quality index MAASTRICHTIAN Statistical Analysis giS
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低GI枸杞杂粮代餐粉的体外消化特性
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作者 田玲丽 马娇 +2 位作者 刘军 范艳丽 刘敦华 《食品工业科技》 CAS 北大核心 2024年第12期342-350,共9页
为探究低血糖生成指数(Glycemic index,GI)枸杞杂粮代餐粉的体外消化特性,本研究对各原料粉及代餐粉的基本组分、吸水率及吸水膨胀率、淀粉组分、淀粉水解率及估计血糖生成指数(Estimate Glycemic index,eGI)值进行测定与分析,并通过体... 为探究低血糖生成指数(Glycemic index,GI)枸杞杂粮代餐粉的体外消化特性,本研究对各原料粉及代餐粉的基本组分、吸水率及吸水膨胀率、淀粉组分、淀粉水解率及估计血糖生成指数(Estimate Glycemic index,eGI)值进行测定与分析,并通过体外模拟胃肠消化方法对比分析了各原料粉及代餐粉中蛋白质水解率、总酚含量、黄酮含量及抗氧化活性的变化。结果表明,代餐粉中脂肪和粗纤维含量相较于各原料粉处于偏低水平。各原料粉及代餐粉的高温吸水率为常温吸水率的2倍左右,其中代餐粉吸水率最低(常温条件下吸水率为0.27%±0.05%,高温条件下吸水率为0.59%±0.05%)。代餐粉中快速消化淀粉含量(40.4%±0.003%)及eGI值(23.4)相较于各原料粉均达到最低,而慢消化淀粉和抗性淀粉含量均相对较高。体外模拟胃肠消化实验中,各原料粉及代餐粉蛋白质水解率均逐渐升高且水解主要以胃部为主,其中代餐粉蛋白水解率相对较高;总酚含量在胃肠消化期间均呈上升趋势且代餐粉在消化结束时含量达到最高(7.26 mg/g)。黄酮含量在模拟胃消化过程中明显增加,而在模拟肠消化中含量下降。DPPH自由基和ABTS+自由基清除率在模拟胃消化过程中随时间延长显著(P<0.05)上升,而在模拟肠消化过程中随时间延长呈先上升后降低趋势,但整体变化幅度较为平缓。综上所述,枸杞杂粮代餐粉适合作为低GI原料或产品且具有良好的抗氧化能力,对于杂粮制品的开发具有一定指导的意义。 展开更多
关键词 gi 杂粮 枸杞 代餐粉 体外消化特性
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Compressive near-field millimeter wave imaging algorithm based on Gini index and total variation mixed regularization
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作者 Jue Lyu Dong-Jie Bi +7 位作者 Bo Liu Guo Yi Xue-Peng Zheng Xi-Feng Li Li-Biao Peng Yong-Le Xie Yi-Ming Zhang Ying-Li Bai 《Journal of Electronic Science and Technology》 CAS CSCD 2023年第1期65-74,共10页
A compressive near-field millimeter wave(MMW)imaging algorithm is proposed.From the compressed sensing(CS)theory,the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-... A compressive near-field millimeter wave(MMW)imaging algorithm is proposed.From the compressed sensing(CS)theory,the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-sampled sparse data.The Gini index(GI)has been founded that it is the only sparsity measure that has all sparsity attributes that are called Robin Hood,Scaling,Rising Tide,Cloning,Bill Gates,and Babies.By combining the total variation(TV)operator,the GI-TV mixed regularization introduced compressive near-field MMW imaging model is proposed.In addition,the corresponding algorithm based on a primal-dual framework is also proposed.Experimental results demonstrate that the proposed GI-TV mixed regularization algorithm has superior convergence and stability performance compared with the widely used l1-TV mixed regularization algorithm. 展开更多
关键词 Millimeter wave(MMW) Compressed sensing(CS) gini index(gi) Total variation(TV) Signal processing Image reconstruction
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时变温差工况下直流GIL/GIS盆式绝缘子动态电场畸变抑制 被引量:2
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作者 杜伯学 姚航 +1 位作者 梁虎成 董佳楠 《电工技术学报》 EI CSCD 北大核心 2024年第9期2851-2859,共9页
为了优化时变温差工况下直流GIL/GIS盆式绝缘子的沿面电场分布,基于表层电导梯度材料(σ-SFGM)设计了以室温(RT)电场均化为目标的RT-SFGM绝缘子与兼顾不同温度梯度(GT)条件的GT-SFGM绝缘子。迭代优化后,RT-SFGM绝缘子的涂层厚度从导体... 为了优化时变温差工况下直流GIL/GIS盆式绝缘子的沿面电场分布,基于表层电导梯度材料(σ-SFGM)设计了以室温(RT)电场均化为目标的RT-SFGM绝缘子与兼顾不同温度梯度(GT)条件的GT-SFGM绝缘子。迭代优化后,RT-SFGM绝缘子的涂层厚度从导体到外壳梯度减小,而GT-SFGM绝缘子的凸面涂层厚度则呈现U型梯度分布。室温条件下,均匀绝缘子的凹面高压三结合点处电场畸变严重,相同位置处的RT-SFGM绝缘子与GT-SFGM绝缘子电场强度分别下降了53.3%和49.5%。随着高压导体温度的上升,绝缘子最大电场位置逐渐向接地外壳附近转移。在40℃温差条件下,GT-SFGM绝缘子的电场畸变抑制效果明显优于RT-SFGM绝缘子,最大电场强度下降59.2%。在负荷加载与负荷波动工况下,GT-SFGM绝缘子的电场变化率分别仅为7%与13.1%,可实现时变温差工况下绝缘子直流电场分布的稳定控制。 展开更多
关键词 直流 giL/giS绝缘子 表面电导梯度材料 时变温差 电场均化
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